(Sorry for the re-post, I originally put this in the wrong forum.)

More specifically -- it’s running rich.

My ’93 945T tripped the check engine light. The codes indicated
-missing signal from O2 sensor
-lean/rich condition at idle
-lean/rich condition under load

A few days later I began experiencing an extremely rich condition – the exhaust was black and it was blowing black soot out the tailpipe. I changed the O2 sensor, and no change. Pulled the vacuum line from the Fuel Pressure Regulator, and there was no change in idle, and no fuel coming out the vacuum nipple. I still made the assumption it was the FPR, so ordered a new one (will be arriving soon.)

The car sat for a few days, then I needed to use it. Remarkably, the extreme rich condition was no longer present. It would still trip the CEL, but the car seemed to be running quite well. The intermittent nature of the problem now has me thinking it could be something electrical as opposed to the FPR. How could a FPR fail intermittently?

Another odd observation: the trip odometer has always required that you push it quite hard to reset. Now I notice pressing the reset button made the CEL come on and off – as if the pressing on the button was flexing the circuit board and causing loss of contact.

Any thoughts are appreciated.

--
Jeff Pierce (Post back with your results... it's what makes this forum work.)